This continuing project has tracked and examined development and use of voluntary binding arbitration for resolution of medical malpractice claims. Early exploratory work included identification and review of all legislation specifically authorizing malpractice arbitration, court opinions on its constitutionality, and sponsored programs or plans for its use. Long available on some basis in every state, malpractice arbitration has since 1975 become widely used in California and Michigan. By 1979, the project had developed a unique computer data base for research on medical malpractice arbitration cases. Available to other researchers, this data base is now being expanded to include 300 cases. Under the current project these data will be used to produce the first quantitative studies of malpractice arbitration cases. Employing forum comparison methodology developed as the project progressed, it will in 1981 be used to compare malpractice cases from the arbitration and court forums, respectively, in southern California and in Michigan.